Pokemon 2017 SM#4+ GX Battle Boost Steenee reverse holofoil card. It was only available inside random booster packs of the SM#4+ GX Battle Boost series that was released in Japan, in October, 2017.
Card #: 023/114
Type: Reverse Holofoil
Condition: Mint condition. Never been played with. No noticeable creases, dents, scratches or whitening on edges of card.